For quick reference to learn Java servlet with eclipse, check out the following references:
1. from http://www.javatpoint.com/creating-servlet-in-eclipse-ide
2. http://theopentutorials.com/examples/java-ee/servlet/how-to-create-a-servlet-with-eclipse-and-tomcat/
3. http://java.keicode.com/lang/web-tomcat.php
4. http://www.srccodes.com/p/article/3/Tomcat-Hello-World-Servlet-using-Eclipse-IDE